In a Jenkins Pipeline script, how do I assign a path with a space to an environment variable?

Question

I'm assigning a path with a space in it to an environment variable using the following syntax:

environment {
   ZIP_HOME = "C:\\Program Files\\7-Zip"
}

I'm trying to use 7-Zip to zip my files and using the variable as the path to the 7-Zip executable.

bat "%ZIP_HOME%\\7z a programdata-${BUILD_NUMBER}.zip ${WORKSPACE}/Staging/programdata"

I also tried putting braces around ZIP_HOME.

bat "${ZIP_HOME}\\7z.exe a programdata-${BUILD_NUMBER}.zip ${WORKSPACE}/Staging/programdata"

I get the following message in the console output:

   'C:\Program' is not recognized as an internal or external command

I also tried putting single quotes around 'Program Files' within the path above but get the same message.

The syntax I used for the bat "{ZIP_HOME}\7z is an answer I found on this site but it didn't work for me.

Thank you in advance.